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Client-Server Architecture Client-server architecture, a model prevalent in computer networks, involves a central server, also referred to as the host computer, acting as the hub for multiple clients, or remote processors, that initiate service requests. Using the interface provided by client computers, users can request services from the server and observe the corresponding responses. Servers await client requests before providing replies. A client, any machine sending a request to the server, can be illustrated when visiting a website. In this scenario, the user is the client making the request. In client-server architecture, a central server (or host computer) serves as the focal point for various clients (or distant processors), while the server itself processes and responds to client requests. In the website example, the client requests the webpage, and the server delivers it in response. Operation of the Client-Server System When a client seeks data from a server, it first uses

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Linux Network and Process Management  In Linux, a process is an active program running under a unique Process ID (PID), having its own allocated resources. Processes can be in different states: Running: Actively executing code. Ready: Awaiting CPU time in a queue. Sleeping: Temporarily paused, waiting for an event or process. Stopped: Halted intentionally by user or system. Zombie: Completed but not yet cleaned up.   To manage processes: Use "ps" to view a list of running processes. "ps aux" for a detailed system-wide process list. "ps aux | grep username" to filter by username. View detailed process info with "/proc/PID/status." "top" provides real-time process monitoring. "kill" command stops a process (e.g., "kill <PID>"). For system services, use "systemctl" (e.g., "sudo systemctl status service_

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LINUX FILE SYSTEM One essential part of the operating system is the Linux file system. It offers a hierarchical data management and organization system. Root Directory: The root directory ("/") is the top-level directory in the Linux file system. Files and subdirectories are found in directories. Data management: Linux file system maintains metadata, sizes, creation dates, and file names. It is responsible for ownership, security, and permissions.   Representation and Organization of Storage Resources: Disk space is allocated for files and directories. It also maintain Directory structure and store Metadata for each file. Pathnames: A pathname is a text string made up of one or more names separated by forward slashes(/) e.g: ./etc/ passwd,/var/log/auth.log, assignment 02 /check, etc. examples of pathnames: ●       /home ●       /etc/passwd ●       usr / wc ●       /var/ ntpstats loopstats Change directory using a relative path:  $pwd /home/kt $cd abc  

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  Basic Commands in Linux ls: It shows the files/directories in the current directory ls -R :It shows all the files not only in directories but also subdirectories. ls -al :Gives detailed information of the files ls -a: Shows all the hidden files cat: Used to display text files,copy ,combine, and create new text files Cat > file Add content crtl + d to return rm: Removes files from the system without confirmation. mv: Move file to a different directory. mv commands needs super user/ root user. sudo - allow a regular user to run programs with the security privileges of the super user or root user. mv: it can also used to rename files or directories mkdir: Creates sub directory in current directory. Syntax: mkdir directory name. To create directory inside other directory use mkdir /other directory name/new Directory rmdir: removes an empty directory. grep (global regular expression print)   :Used to search text in files and print that matches the gi

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 Introduction to Linux Linux  is an operating system and  Android is powered by the linux operating system.   OS is software that manages the communication between the software and its hardware. To manage files in Linux OS we can use : Terminal (Command Line Interface - CLI) File Manager (Graphical User Interface-GUI) Why do we use a Command-line Interface? Commands offer more options and are flexible. More commands to copy and upload files in GUI but in the case of CLI a single command can do it. CLI load fast and do not consume RAM like GUI. There are two ways to launch CLI on Ubuntu; Go to the Das and type terminal Or Press ctrl+alt+t   Once the CLI is launched the picture will be shown: First Part - user name. Eg: guru Second part - hostname. Eg:99  (Helps to identify a computer over the network). Third part - Computer name. Eg: VirtualBox Fourth part - Simple separator. Eg: " : " fifth part - Home Directory.

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              Container Technology Container A container is a generic software package that combines the application's code and all of its dependence to provide a quick and reliable transition between computers environments. Containers offer an infrastructure that makes it possible to launch applications with minimal and immutable packaging. A container image contains the code, runtime, system, tools, system libraries, and setting.   Linux Container A group of one or more isolated processes on the Linux operating system is referred to as a container. Because Linux containers are portable and consistent as they move from development to testing to production, all the files required to run them are delivered from a separate image.  Because of this, they operate far more quickly than development pipelines that rely on simulating conventional testing environment.   Why Use Linux Container? Consider creati

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  C02: Network Protocol  An established set of guidelines that govern how data is transferred between various devices connected to the same network is known as a  network protocol .  At the top of the OSI model is the application layer. Users interact with each other through this layer. The user receives services from it. Any kind of application or communication process requires the performance of a variety of functions by the application layer. Application Layer Protocol 1. HTTP HTTPS, which stands for Hypertext Transfer Protocol Secure, is the more secure form of HTTP, which is what HTTP stands for. Data from the World Wide Web is accessed via this protocol.  Pages in a text document are linked together using the well-organized documentation system known as hypertext. The client-server concept is the foundation for HTTP. It establishes connections using TCP. Due to the statelessness of the HTTP protocol, the server does not k